<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <script>
    function bubble(arr) {
      for(var i = 0; i < arr.length - 1; i++) {
        for(var j = 0; j < arr.length - 1 - i; j++) {
          if(arr[j] < arr[j +1]) {
            var temp = arr[j]
            arr[j] = arr[j+1]
            arr[j+1] = temp
          }
        }
      }

      return arr
    }

    var arr = [2, 3, 1, 5, 4]
    var newArray = bubble(arr)

    console.log(newArray)
  </script>
</body>
</html>